This invention relates to grate risers for catch basins of the type shown and described in my U.S. Pat. No. 4,544,302 entitled CATCH BASIN GRATE RISER.
Conventional catch basins are formed with generally rectangular frames having at least two similar opposing frame sections each of which carries an inwardly projecting horizontally support flange. The grates associated With the frames include a plurality of parallel spaced apart elongated grate members which are adapted to rest at opposite end portions on the aforementioned frame flanges. The grates are conventionally held in position within the frame by gravity.
When an associated road surface is repaved, there are three conventional techniques employed in raising catch basins to the level of the top surface of the new pavement or overlay.
The first of the conventional techniques requires the aforementioned parts of the catch basin to be removed together with a precast concrete supporting member which is usually associated therewith. Bricks or the like may then be employed to support the precast concrete member at the desired elevated position whereupon the concrete member, the catch basin frame, and the grate are repositioned With the bricks therebeneath.
A second technique or method involves the welding of sections of angle iron or the like to the opposite end portions of the grate at lower portions thereof. This results in the grate being elevated to the desired level while the frame remains in its original position. At its end portions the grate is of course exposed to paving material which may find its way between the grate members and this of course creates a detrimental condition.
A third method involves the welding of a new frame to the top of the existing frame of the catch basin. This of course accommodates only the raising of the catch basin elements an increment equal to the height of the original frame and grate. Thus, if a conventional 31/2 inch frame and grate are employed, the elevation thereof can only be 31/2 inches. The paving on the other hand may have a desired thickness of only 11/2 inches.
As will be apparent, each of the foregoing techniques or methods involves an inefficient and time consuming operation. The removal and replacement of all or part of a catch basin of course requires a substantial expenditure in time. A resulting delay in the paving operation occurs and it is also necessary to employ heavy equipment when the concrete member is removed. At a minimum, and in the practice of each of the foregoing methods, operations such as welding or brick laying are involved. This may require considerable time and expense and even a possible transfer of parts to a welding shop etc.
The grate riser of the aforementioned patent may be installed in a highly efficient and rapid operation and there is no interference Whatsoever With the associated road paving operation. The grate is merely removed from the catch basin, the grate riser is deposited within the frame of the catch basin and the grate is then returned to its initial position except for the elevation thereof by the grate riser. That is, the grate is maintained precisely in a desired position horizontally but is elevated by the grate riser to the exact height required by the thickness of the new pavement.
As will be apparent, the patented grate riser is a highly efficient tool in a repaving operation and has found wide acceptance. There is, however, one major problem which arises in the use of the grate riser. Only a single repavement or pavement overlay can be accomplished.
It is the general object of the present invention to provide an improved grate riser assembly wherein two or more grate risers can be stacked atop one another to accommodate two or more repaving operations or pavement overlays.